择伐干扰对小兴安岭阔叶红松林土壤磷形态及有效性的影响  

Effects of selective cutting on soil phosphorus forms and availability in Korean pine broad-leaved forest in Xiaoxing'an Mountains of China

作　　者：张鑫[1] 谷会岩[1] 陈祥伟[1] 

机构地区：[1]东北林业大学林学院,哈尔滨150040

出　　处：《应用生态学报》2018年第2期441-448,共8页Chinese Journal of Applied Ecology

基　　金：林业公益性行业科研专项(201404303)资助~~

摘　　要：以小兴安岭原始阔叶红松林(对照)和经过轻度、中度和强度择伐干扰后形成的天然林林地表层(0~10 cm)土壤为对象,采用Sui修正后的Hedley磷素分级法对土壤样品进行连续浸提,研究不同林地土壤各形态磷素含量的差异及变化规律,分析择伐干扰对阔叶红松林土壤磷素有效性的影响.结果表明:各林地土壤全磷含量为1.09~1.66 g·kg^(-1),以原始阔叶红松林最高,强度择伐林地最低,且不同处理间差异显著;各林地土壤有效磷和磷素活化系数的变化幅度分别为7.26~17.79 mg·kg^(-1)和0.67%~1.07%,均表现出随择伐强度的增加而显著降低;除酸溶性有机磷(HCl-P_ o)外,经过择伐干扰的林地与原始林相比,土壤水溶性磷(H_2O-P_ i)、碳酸氢钠磷(NaHCO_3-P)、氢氧化钠磷(NaOH-P)、酸溶性无机磷(HCl-P_i)和残留磷(Residual-P)含量均表现出随择伐强度的增加而降低的趋势.各组分间以水溶性(H_2O-P_ i)与土壤有效磷的相关系数最大(0.98),但其含量仅占磷素总量的1.5%~2.2%;氢氧化钠磷(NaOH-P)含量占磷素总量的48.0%以上,是土壤的潜在磷源.可以认为,择伐干扰通过显著降低土壤无机态磷和氢氧化钠有机磷(Na OH-P _o)的含量,限制和影响了阔叶红松林土壤有效磷及潜在磷源的供应水平,并且其表现出随择伐强度的增加而逐渐降低的趋势.In order to clarify the effects of selective cutting on soil phosphorus availability in Korean pine broad-leaved forest, surface soil （0-10 cm） samples from original Korean pine broad-leaved forest and natural forests with mild, medium and intensive cutting disturbances were collected. The Sui modified Hedley phosphorus fractionation method was used to continuously extract soil samples and analyzed the differences and changes of soil phosphorus fractions from different experimental stands. The results showed that the soil total phosphorus content of Korean pine broad-leaved forest varied from 1.09 to 1.66 g . kg-1 , with the original stand and intensive cutting disturbance stand being the maximum and minimum one, respectively. The differences of soil total phosphorus content among cutting disturbance levels were significant. The Olsen phosphorus and phosphorus activation coefficients changed with an amplitude of 7.26-17.79 mg . kg-1 and 0.67%-1.07%, respectively. Both of them significantly decreased with the increase of selective cutting disturbance level. The concentrations of all P fractions except HCl-Po, i.e., H2O-Pi, NaHCO3-P, NaOH-P, HCl-Pi, Residual-P, decreased with increasing cutting disturbance levels compared with original forest. The correlation coefficient between H2O-Pi and soil Olsen phosphorus was the highest （0.98）, though it only accounted for 1.5%-2.2% of the total phosphorus. NaOH-P content contributed to more than 48.0% of the total phosphorus, acknowledged as the potential source of soil phosphorus. In conclusion, selective cutting disturbance could constrain phosphorus storage and soil phosphorus availability of the Korean pine broad-leaved forests by significantly reducing the content of soil inorganic phosphorus and NaOH-Po, and such trends were positively dependent on the intensity of selective cutting.

关 键 词：阔叶红松林 择伐干扰 土壤磷 Hedley磷素分级 磷素有效性 

分 类 号：S714[农业科学—林学]